Effect of D-serine on Anxiety-like Behavior and Spatial Learning Ability in GC Rats Selected for the Predisposition to Catatonic Reactions

Evidence of an important role of D-serine, a co-agonist of the glycine site of NMDA receptor, in pathogenesis of psychiatric disorders continues to accumulate. Possible ways of using D-serine for correcting cognitive impairments and negative symptoms in schizophrenia are widely discussed. Given the therapeutic potential of D-serine, it seems important to investigate its effect on experimental models of pathological behavior. This study was carried out on GC rats, proposed as a model of catatonic disorders, and Wistar rats, undisposed to catatonic reactions. In numerous studies, D-serine is used at fairly high doses, although it has been established that high doses of D-serine elicit adverse side effects. The aim of this study was to investigate the effect of low D-serine doses on the behavior of GC rats and control Wistar rats in the light–dark box and elevated plus maze tests, as well as on their learning ability in the Barnes maze. It was found that intraperitoneal injection of 50 mg/kg D-serine had both anxiolytic and procognitive effects on Wistar rats. In GC rats, a D-serine dose of 100 mg/kg reduced locomotor activity in the elevated plus maze test, while at 50 mg/kg, D-serine reduced locomotor activity in the Barnes maze, but did not affect escape latency.